Languages like Modula-3 or Oberon would have taken over the world of systems programming.
Unfortunately there are too many non-believers for systems programming languages with automatic resource management to take off as they should.
Despite everything, kudos to Apple for pushing Swift no matter what, as it seems to be only way for adoption.
Or those languages had other (possibly unrelated) problems that made them less attractive.
I think that in a high-economic-value, competitive activity such as software, it is tenuous to claim that something delivers a significant positive gain and at the same time that that gain is discarded for irrational reasons. I think at least one of these is likely to be false, i.e. either the gain wasn't so substantial or there were other, rational reasons to reject it.
Even for teams further toward the right of the bell curve, historical contingencies have a greater impact than they do in more grounded engineering fields. There are specialties of course, but nobody worries that when they hire a mechanical engineer someone needs to make sure the engineer can make designs with a particular brand of hex bolt because the last 5 years of the company’s designs all use that brand.
Projects like Midori, Swift, Android, MaximeVM, GraalVM, only happen when someone high enough is willing to keep it going until it takes off.
When they fail, usually it is because management backing felt through, not because there wasn't a way to sort out whatever was the cause.
Even Java had enough backing from Sun, IBM, Oracle and BEA during its early uncertainty days outside being a language for applets, until it actually took off on server and mobile phones.
If Valhala never makes it, it is because Oracle gave up funding the team after all these years, or it is impossible and it was a waste of money?
It's just pig-headedness by Apple, nothing more.
Instead Swift was designed around the use-cases the team was familiar with, which would be C++ and compilers. Let's just say that the impedance between that and rapid UI development was pretty big. From C++ they also got the tolerance for glacial compile times (10-50 times as slow as compiling the corresponding Objective-C code)
In addition to that they did big experiments, such as value semantics backed by copy-on-write, which they thought was cool, but is – again – worthless in terms of the common problem domains.
Since then, the language's just been adding features at a speed even D can't match.
However, one thing the language REALLY GETS RIGHT, and which is very under-appreciated, is that they duplicated Objective-C's stability across API versions. ObjC is best in class when it comes to the ability to do forward and backwards compatibility, and Swift has some AWESOME work to make that work despite the difficulties.
